Van Allen Probes Bibliography is from August 2012 through September 2021 Notice:
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Lifetimes of Relativistic Electrons as Determined From Plasmaspheric Hiss Scattering Rates Statistics: Effects of ωpe/Ωce and Wave Frequency Dependence on Geomagnetic Activity
Author | Agapitov, O.; Mourenas, D.; Artemyev, A.; Claudepierre, S.; Hospodarsky, G.; Bonnell, J.; |
Keywords | electron lifetimes; plasmasphere; hiss waves; wave-particle interactions; Van Allen Probes |
Abstract | Whistler-mode hiss waves generally determine MeV electron lifetimes inside the plasmasphere. We use Van Allen Probes measurements to provide the first comprehensive statistical survey of plasmaspheric hiss-driven quasi-linear pitch-angle diffusion rates and lifetimes of MeV electrons as a function of L*, local time, and AE index, taking into account hiss power, electron plasma frequency to gyrofrequency ratio ωpe/Ωce, hiss frequency at peak power ωm, and cross correlations of these parameters. We find that during geomagnetically active periods with hiss observations, ωpe/Ωce and ωm decrease, leading to faster electron loss. We demonstrate that spatiotemporal variations of ωm and ωpe/Ωce with AE, together with wave power changes, significantly affect MeV electron loss, potentially leading to short lifetimes of less than 1 day. A parametric model of MeV electron lifetime driven by AE for L > 2.5 up to the plasmapause is developed and validated using Magnetic Electron Ion Spectrometer (MagEIS) electron flux decay database. |
Year of Publication | 2020 |
Journal | Geophysical Research Letters |
Volume | 47 |
Number of Pages | e2020GL088052 |
Section | |
Date Published | 05/2020 |
ISBN | |
URL | https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2020GL088052 |
DOI | https://doi.org/10.1029/2020GL088052 |